[PATCH RT] net: Add missing xmit_lock_owner hunks.

[Sebastian Andrzej Siewior]

The patch
	net: move xmit_recursion to per-task variable on -RT

lost a few hunks during its rebase.

Add the `xmit_lock_owner' accessor/wrapper.

Reported-by: Salvatore Bonaccorso <carnil@xxxxxxxxxx>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
 include/linux/netdevice.h | 29 +++++++++++++----------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 7b34ce34114ac..ce19befe4d87d 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3882,17 +3882,17 @@ static inline u32 netif_msg_init(int debug_value, int default_msg_enable_bits)
 #ifdef CONFIG_PREEMPT_RT_FULL
 static inline void netdev_queue_set_owner(struct netdev_queue *txq, int cpu)
 {
-	txq->xmit_lock_owner = current;
+	WRITE_ONCE(txq->xmit_lock_owner, current);
 }
 
 static inline void netdev_queue_clear_owner(struct netdev_queue *txq)
 {
-	txq->xmit_lock_owner = NULL;
+	WRITE_ONCE(txq->xmit_lock_owner, NULL);
 }
 
 static inline bool netdev_queue_has_owner(struct netdev_queue *txq)
 {
-	if (txq->xmit_lock_owner != NULL)
+	if (READ_ONCE(txq->xmit_lock_owner) != NULL)
 		return true;
 	return false;
 }
@@ -3901,17 +3901,19 @@ static inline bool netdev_queue_has_owner(struct netdev_queue *txq)
 
 static inline void netdev_queue_set_owner(struct netdev_queue *txq, int cpu)
 {
-	txq->xmit_lock_owner = cpu;
+	/* Pairs with READ_ONCE() in __dev_queue_xmit() */
+	WRITE_ONCE(txq->xmit_lock_owner, cpu);
 }
 
 static inline void netdev_queue_clear_owner(struct netdev_queue *txq)
 {
-	txq->xmit_lock_owner = -1;
+	/* Pairs with READ_ONCE() in __dev_queue_xmit() */
+	WRITE_ONCE(txq->xmit_lock_owner, -1);
 }
 
 static inline bool netdev_queue_has_owner(struct netdev_queue *txq)
 {
-	if (txq->xmit_lock_owner != -1)
+	if (READ_ONCE(txq->xmit_lock_owner != -1))
 		return true;
 	return false;
 }
@@ -3920,8 +3922,7 @@ static inline bool netdev_queue_has_owner(struct netdev_queue *txq)
 static inline void __netif_tx_lock(struct netdev_queue *txq, int cpu)
 {
 	spin_lock(&txq->_xmit_lock);
-	/* Pairs with READ_ONCE() in __dev_queue_xmit() */
-	WRITE_ONCE(txq->xmit_lock_owner, cpu);
+	netdev_queue_set_owner(txq, cpu);
 }
 
 static inline bool __netif_tx_acquire(struct netdev_queue *txq)
@@ -3938,8 +3939,7 @@ static inline void __netif_tx_release(struct netdev_queue *txq)
 static inline void __netif_tx_lock_bh(struct netdev_queue *txq)
 {
 	spin_lock_bh(&txq->_xmit_lock);
-	/* Pairs with READ_ONCE() in __dev_queue_xmit() */
-	WRITE_ONCE(txq->xmit_lock_owner, smp_processor_id());
+	netdev_queue_set_owner(txq, smp_processor_id());
 }
 
 static inline bool __netif_tx_trylock(struct netdev_queue *txq)
@@ -3947,23 +3947,20 @@ static inline bool __netif_tx_trylock(struct netdev_queue *txq)
 	bool ok = spin_trylock(&txq->_xmit_lock);
 
 	if (likely(ok)) {
-		/* Pairs with READ_ONCE() in __dev_queue_xmit() */
-		WRITE_ONCE(txq->xmit_lock_owner, smp_processor_id());
+		netdev_queue_set_owner(txq, smp_processor_id());
 	}
 	return ok;
 }
 
 static inline void __netif_tx_unlock(struct netdev_queue *txq)
 {
-	/* Pairs with READ_ONCE() in __dev_queue_xmit() */
-	WRITE_ONCE(txq->xmit_lock_owner, -1);
+	netdev_queue_clear_owner(txq);
 	spin_unlock(&txq->_xmit_lock);
 }
 
 static inline void __netif_tx_unlock_bh(struct netdev_queue *txq)
 {
-	/* Pairs with READ_ONCE() in __dev_queue_xmit() */
-	WRITE_ONCE(txq->xmit_lock_owner, -1);
+	netdev_queue_clear_owner(txq);
 	spin_unlock_bh(&txq->_xmit_lock);
 }
 
-- 
2.34.1